I'm glad you enjoyed the dictation activities. Here's another one that I hope will go down well.
Find a short text slightly below the level of what your students can understand. Find one that is about 100 words in length. Introduce the topic of the text and engage the students in the topic. Pre-teach any difficult vocabulary, focus on pronunciation of the new words.
You can then read the text to the students at the speed you would use in normal conversation and using normal articulation. Students write down anything they hear. Allow them time to compare and note down anything their classmates heard. You can then repeat the dictation, still at normal speed. Allow students time to compare again. Continue with this until the students have the text almost complete. While students are comparing, you can monitor and help them guess what the blanks are. For example, "I haven't seen her f.... two weeks"; guide them towards the idea that the present perfect is often followed by "for". Guide them towards the answer without giving too much away. When you think the students have had enough, give them a copy of the text to check their answers. You can then follow up the dictation with a discussion of the topic.
This activitiy can take a long time and the benefits to students are many. They practise predicting what the missing words are; they get practice in listening for specific information; they practise making the connection between spoken and written language, including the use of the schwa.